Acquisitions Business Acquisition - Proforma Information (Details) - USD ($)	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Business Combinations [Abstract]
Business Acquisition, Pro Forma Revenue	$ 2,904,253,000	$ 2,977,612,000
Business Acquisition, Pro Forma Net Income (Loss)	$ 272,985,000	$ (79,347,000)
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Net of Tax, Per Share, Basic	$ 2.63	$ (0.74)
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Net of Tax, Per Share, Diluted	$ 2.62	$ (0.74)

Per basic share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

Per diluted share amount of pro forma income from continuing operations, after tax, as if the business combination had been completed at the beginning of a period.

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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No definition available.

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